Nanostructured silicon and silicon-germanium are attractive materials for a variety of applications due to their abundance, stability and low toxicity. Recently, nanostructured silicon and silicon-germanium have been utilized in several applications from thermoelectrics, photovoltaics, solar cell batteries and biological imaging. Several methods exist for producing silicon, such as the pyrolysis of silane, pulsed laser ablation, MOCVD, MBE, plasma etching and electrochemistry. However, these aforementioned methods are inherently limited due to the expense, complex equipment, toxic precursors and difficulty of scaling up the reactions to produce on a commercial scale. An alternative method of producing nanostructured silicon involves a solution-based synthetic technique. The drawback of the solution-based synthetic technique is the use of a long chain hydrocarbon capping ligand necessary to prevent particle agglomeration. The capping ligand, however, adds additional processing steps prior to use of the nanostructured silicon for applications where electron transfer is critical, such as in thermoelectrics or in solar cells.
Thus, there is a need for a new method for producing nanostructured silicon and nanostructured silicon-germanium, which is relatively inexpensive, does not require expensive equipment or toxic precursors and is capable of being scaled-up efficiently to produce commercial amounts of the reaction product.